swing-arm - options ?

OK folks, I've conferred with Super-Tommy the forum lurker and as usual I had my wires crossed.  The swingarm he has was sold to him "back in the day" by Windy Corner, and was described as a Spondon.  It seems identical to Mark's one, so I think problem solved.  Mark - I note you have an underslung caliper mount so this should not be a problem, but tom's has fractured around the brake stay mount (as do the JMC's) so do keep an eye out for cracks there.
spondonswing2.jpg

spondonswing1.jpg

Cheers
SteveB
 
congratulations to SteveB !!  (goodjob)

and Harry.L's comment was a bit more than a guess.

that swing-arm is identical to what i got from Ken.Mc.  a Spondon swing-arm.  kool.
good to have friends, eh.    (cheers)
 
Marko,
No worries, glad I could help out.  Please do check for cracks in the region of the brake stay lug regularly!  Even if you're not using the lug now, it was probably used in the swingarms former life and localised stresses might have given the material in that area a hard time.  Both these and JMC's will crack all the way around the box section and eventually fall in half, which might get a bit interesting.
Cheers
SteveB
 
thanks Steve.
reckon stripping all the paint off and getting it polished up was a good investment re crack detection eh.
was gunna hack that brake lug off, but thought i might just leave it alone.
cheers,  Mark
 
reply today from Roger Winterburn, Windy Corner;

" Hi Mark, Nice to hear from you after all this time. I have actually "Turned Back the Clock" recently  and returned
            to the preparation , and renovation of Laverda machines!
            Its looking good so far with six Triples in the workshop undergoing various levels of work.

            Re. the alloy swing arm pictured, it is indeed one of our Windy Corner alloy braced units, we supplied
            box section alloy (with and without "A" frame bracing) and a superb round steel tube (with "A"frame).
            I was never keen on the Metmachex units as the eccentric adjusters lifted and lowered the bike so much
            that the ride height changed too much...plus the centre stand didnt work as well as Laverda intended!  
            Well if I can be of any more help to you please contact me.
            Regards , Roger. "


reckon i agree with the eccentric adjuster comment.  they look trick, but can stuff the ride height a bit (a lot).
was good to get a prompt reply back from Roger.  ya can take da man out of Laverda, but ya can't take Laverda out of da man !!
cheers

,,  and here's da link;  
http://www.windycorner.co.uk/
30 years ago, dealing with Roger at Windy Corner, half way around the world, was always good.  (and not by www. !!)
 
This is one of the early Metmachex swingarms.  I lent them my bike back in the early 80s...dropped it off with them on a wednesday afternoon and on the friday, Bill who owned the place rang me to say I could come and pick my bike up, as they'd done with it...I rode back home with the new swinger fitted, not a bad turnaround.

In those days swingarms were a big part of there business, it was the early 80s afterall, but when I last went to the new factory they'd obviousley moved on to much bigger things, and Bill (whose now retired, Seans his lad) reckoned making swingarms was just a hobby, but speaking to Sean it was clear he was keen to get back into them, as he spent quite some time showing me some trick tubular swingers he'd made up for someone who was classic racing with a few GS1000s,  reckon if anyones wanting to spend some dosh on a swingarm, no chance of em doin a JMC on yer, it's a proper place. 

IMGP2398.JPG


 
Blimey......looking at that last picture, I can see what Roger meant about the adjuster altering the ride height.  Wonder how it works out in real life?
 
It's also sitting on a raised stone slab which might mask the real level of the rear end.
 
It worked really well.. the rear spindle was a long bolt that was keyed into the round carriers, the spindle only moved about 15degrees either side of top...if your stand didnt function right it meant your chain was shagged..
 
The change in riding hight is causing several issues:

-different handling
-your legs might be to short to securely touch ground at the traffic light or other stops
-your bike might not stay on the center stand and role off

If you have adjustable shock lengths, this can be compensated. Still, I don't see a benefit in this system over the classic one. See that - I think - none of the current bikes has this adjuster system. There must be a reason for that, and that for sure isn't cost...
 
Maybe that's one reason few modern bikes have centrestands.

I see it as a free ride height adjuster. Folk pay fortunes for such.
Just rotate the adjusters 180? and you have about 20mm or more increased ride height. Saves dropping the yokes down the stanchions (thereby increasing ground clearance at the alternator)
 
Reason it was developed was, apart from it looking quite funky compared to the alternative at the
time, was to aid quick chain adjustment, remember in those days a big heavy superbike stretched its
chain on a daily basis..
 
I once turned the eccentric adjusters on a Triumph enduro triple to decrease the ride height for a lady friend.  Dropping the stancions kept things level without sacrificing much cornering clearance.  Needed to shorten both stands to keep life easy and space out the chainguard for clearance.

Eccentrics have the stupid tendancy to develope quite a bit of rot between adjusters and swingarm housing, making adjustments and/or wheel removal a royal pain in the arse!  I recently overhauled a Jota with an alloy swinger fitted with eccentrics, took the best part of the morning just to get bloody wheel out, the spindle and eccentrics were corroded solid!

The system calls for close tolerances during manufacture, or it will not allow easy adjusting when assembled.  These close tolerances are the downfall of the system as well.  Once lube is "forgotten", the bike stands untouched for a decade or 2, or road salt finds its way in, it's easier to cut the whole shit out of the frame with an angle grinder!

Look quite clumsy imho anyway.

piet (bolt)
 
Laverdalothar said:
The change in riding hight is causing several issues:
-your legs might be to short to securely touch ground at the traffic light or other stops

get a smaller bike then
my JMC swingarm does not worry me trying to touch the ground, is perfect

 
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